The present invention generally relates to air bags for safety restraint systems and more particularly to an air bag that incorporates a woven fill hose that has greater resistance to bending and twisting than shown in the prior art and one which facilitates mounting of the air bag to the vehicle.
Most curtain air bags in current production include one or more inflatable chambers formed by one or more panels of woven material constructed of nylon or polyester. The air bag is filled by an inflator of known variety. Many air bags utilize a distribution tube that extends from the inflator across the length of the air bag, typically at its top, to distribute inflation gas to various sections of the air bag; this distribution tube has been made of a metal tubing or alternatively by a flexible woven hose not unlike a fire hose. One of the benefits of utilizing rigid tubing is that the assembled module with folded air bag is relatively rigid because of the tube, and somewhat easier for the assembler to manipulate when installing the air bag module into a vehicle than the typical module using a flexible woven tube. Air bag modules that currently utilize a woven hose are more flexible than those modules utilizing rigid tubes and tend to droop and, as such, require a greater level of intervention and care during assembly by the assembler when installing this type of air bag module.
Reference is briefly made to FIGS. 1a-1c which illustrate some of the features of an existing curtain air bag module. In these figures the curtain air bag 202 has been folded and pulled into or placed within a cylindrically shaped, hollow, tearable, flexible cover 200. The cover 200 may be made from a woven piece of material, a non-woven material or other known construction. Mounting tabs 204 extend outwardly from the air bag through slits in the cover 200. Each tab includes a mounting hole 206, enabling the module to be mounted to a fastener such as hooks formed on the roof rail of the vehicle or, alternatively, attached to a roof rail using fasteners, such as bolts or screws that extend through the holes in the roof rail. FIG. 1b shows the module of FIG. 1a twisted one full turn, 360°, about its longitudinal axis. This twisting shortens the distance between adjacent tabs 204. As can be appreciated, twisting may restrict any gas flow passages in the air bag proximate the region being twisted. An air bag module in this condition should not be mounted to the vehicle in this manner. The mounting of a twisted module to the roof rail should not happen during assembly as many flexible covers such as 200 include a line or pattern or words generally noted as 208 and if this line or pattern is broken or interrupted, such as in FIG. 1b, the worker installing the module should recognize the module is twisted. In some situations the twisted module can still be mounted to the roof rail at the desired location as the extending, flexible tabs 204 might be sufficiently long that when stretched outwardly the module can still be mounted to the roof rail, see FIG. 1c. This and other deficiencies are corrected by the present invention.
The present invention includes a woven hose, devoid of extending tabs, which functions as a gas distribution tube. More particularly, the invention comprises: an air bag module including an inflatable air bag configured to receive a gas distribution hose therein, the gas distribution hose comprising a tubular portion and a flat portion integrally formed with the tubular portion, the tubular portion configured to receive inflation gas at one portion and having at least one opening therein to permit the egress of inflation gas; the flat portion of the hose located between the opposing edge borders of the facing panels of the air bag; and a seam or seams or a joint, or seal extends through a main panel and hose to join the hose between the edge borders of the main panel.